Department of Health Services: Updates COVID-19 summary data page

The Wisconsin Department of Health Services (DHS) is updating data displayed on the COVID-19 Summary Data page. The new Wisconsin COVID-19 Summary Statistics dashboard will continue to report COVID-19 cases and deaths, with an emphasis on seven-day averages, and will now also display vaccination rates and disease activity so Wisconsinites can continue to stay informed about the state of the pandemic. The summary dashboard will include the following metrics as seven-day averages:

  • New confirmed cases
  • New probable cases
  • Percent positive by test
  • New deaths

Displaying data as seven-day averages helps smooth out trends over time that may fluctuate day to day based on when data is reported. COVID-19 data will now only be updated Monday through Friday.

“DHS is committed to providing the most up-to-date and relevant COVID-19 metrics to assist local and tribal health departments, local decision-makers, and individuals make informed choices within their communities,” said DHS Secretary-designee Karen Timberlake. “The updated Wisconsin COVID-19 Summary Statistics provide critical information to the public to better understand the status of COVID-19 in our state.”

In addition, DHS has updated the data that feeds information to several of the visualizations on the COVID-19 data pages. To make our data more precise, we have improved our method of reporting daily new confirmed and probable cases and new reported deaths so they are not impacted by ongoing data cleaning and quality assurance efforts. This prevents daily COVID-19 case and death data from appearing artificially low, or even negative, and gives a more accurate account of daily new COVID-19 cases and deaths across Wisconsin. The updated data file used in this new method will be available for download from our data portal(link is external) tomorrow (May 28).

“What we are seeing with these changes is epidemiologists doing their job in real time with very large data sets,” said DHS Deputy Secretary Julie Willems Van Dijk. “As our state’s COVID-19 case and death counts decline, we want to make sure we’re monitoring today’s numbers precisely. Our new method for reporting new confirmed and probable cases and deaths allows data cleaning to continue, while providing a clear daily picture of COVID-19 throughout the state.”

Examples of data cleaning and quality assurance include merging duplicate reports of the same case of COVID-19, reviewing data fields where there are a large number of “unknowns,” and verifying reported data that may result in a case being changed from “probable” to “confirmed” or vice versa. In the case of cleaning “unknowns,” there may be shifts in the categorization of COVID-19 cases or deaths. This shift will be significant the first time this matching process is conducted. This effort is being carried out first among confirmed cases living in group housing and COVID-19 cases by race and ethnicity, with future updates planned for cases among health care workers. This work is similar to prior work we conducted to reduce the number of “unknowns” in our group housing charts.

These ongoing data quality assurance efforts are an important part of providing complete and accurate COVID-19 case and death data. The efforts also reflect a continued commitment to high data integrity and transparent, real-time COVID-19 data. DHS will continue to provide updates on these efforts and how they will enhance COVID-19 data quality in Wisconsin.